Patient interface systems

ABSTRACT

A patient interface structure for delivery of respiratory therapy to a patient includes a front plate configured to conform to the shape of the patient&#39;s face; a mouth cushion defining a breathing chamber and provided to the front plate and configured to seal around the patient&#39;s mouth; and a nasal cushion configured to seal the patient&#39;s nasal airways. The nasal cushion is supported by the mouth cushion, does not contact a bridge of the patient&#39;s nose in use, and extends at least partially into the breathing chamber. A patient interface system includes a patient interface structure and a patient interface structure positioning system configured to position, stabilize and secure the patient interface structure in sealing engagement with the patient&#39;s face.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/876,624, now allowed, filed Mar. 28, 2013, which is the U.S. nationalphase of International Application No. PCT/AU2011/001258 filed 30 Sep.2011 which designated the U.S. and claims the benefit of U.S.Provisional Applications 61/388,357, 61/443,623, 61/457,981, and61/528,524, filed Sep. 30, 2010, Feb. 16, 2011, Jul. 27, 2011, and Aug.29, 2011, respectively, the entire contents of each being incorporatedherein by reference in its entirety.

FIELD OF THE INVENTION

The present technology relates to a patient interface, or mask, systemfor treatment of sleep disordered breathing (SDB).

BACKGROUND

Treatment of sleep disordered breathing (SDB), such as obstructive sleepapnea (OSA), by continuous positive airway pressure (CPAP) flowgenerator systems involves the continuous delivery of air (or otherbreathable gas) pressurized above atmospheric pressure to the airways ofa human via a conduit and a mask. Typically, the mask fits over or inthe mouth and/or nose of the patient. Pressurized air flows to the maskand to the airways of the patient via the nose and/or mouth. Pressurizedair is delivered to the mask by a conduit connected to the CPAP deviceand the mask.

The mask should be comfortable and unobtrusive so that a patient maytolerate therapy and maintain usage. Some patients may prefer a pillowsor prongs type mask (as known in the art), or a nasal mask or a fullface mask. Some patient's may prefer to use one or a combination ofthese masks interchangeably. However, this would require the purchase ofa number of different mask systems, which may be expensive and/or maynot be covered by insurance.

In addition, masks including oro-nasal masks typically include a rigidframe. Patients may not find this comfortable. The frame may alsodislodge the sealing portion of the mask away from the face of thepatient if it is contacted or forced by bed clothing, pillows, etc.

BRIEF SUMMARY

One aspect of the present technology relates to patent interface, ormask, systems that provide integrated nose and mouth seals that are lessobtrusive than currently available systems.

Another aspect of the present technology relates to patient interfacesystems that have reduced part counts compared to currently availablesystems.

A further aspect of the present technology relates to patient interfacesystems, for example oro-nasal masks, that provide a visible mouthregion of the patient.

Still another aspect of the present technology relates to patientinterface systems, for example oro-nasal masks, that do not obstruct thepatient's line of sight.

Further aspects of the present technology relate to patient interfacesystems, for example oro-nasal masks, that are easier and/or moreintuitive to assemble, fit, and use by patients, dealers, andclinicians, and provide improved fitting and sealing.

Yet another aspect of the present technology relates to patientinterface systems, for example oro-nasal masks, that provide sizeselection from remote locations, and without assistance and/orinstruction.

Another aspect of the present technology relates to patient interfacesystems, for example oro-nasal masks, that are consideredphysiologically non-threatening and will increase patient selection ofthe system and adherence to therapy.

Further aspects of the present technology relate to patient interfacesystems, for example oro-nasal masks, that seal the mouth and nasalairways but have no nasal bridge touch points and/or fewer total pointsof contacts with the patient's face than current systems.

Another aspect of the present technology relates to patient interfacesystems, for example oro-nasal masks, that comprises a substantiallyplanar fascia that may provide a visible mouth region of the patient.

Another aspect of the present technology relates to patient interfacesystems, for example oro-nasal masks, that comprises a substantiallycurved and/or smooth fascia that may provide a visible mouth region ofthe patient.

Another aspect of the present technology relates to patient interfacesystems, for example oro-nasal masks, that comprises a substantiallycurved and/or smooth fascia that may have no ridges, connector portionsor other obstructions in the region of the patient's mouth, so that thefascia may provide a visible mouth region of the patient.

Another aspect of the present technology relates to patient interfacesystems, for example oro-nasal masks, that comprises a substantiallysmooth fascia that may have no complex shapes, connector portions orother obstructions in the region of the patient's mouth, so that thefascia may provide a visible mouth region of the patient.

Another aspect of the present technology relates to patient interfacesystems, for example oro-nasal masks, that comprises an air deliverytube connection, the air delivery tube connection positioned on thecushion.

Another aspect of the present technology relates to patient interfacesystems, for example oro-nasal masks, that comprises an air deliverytube connection, the air delivery tube connection positioned on thefascia and offset from the centre of the fascia, that may provide avisible mouth region of the patient.

Another aspect of the present technology relates to patient interfacesystems, for example oro-nasal masks, that are substantially comprisedof flexible components.

Another aspect of the present technology relates to patient interfacesystems, for example oro-nasal masks, that are stabilised at the nosesealing portion separately to the mouth sealing portion.

A patient interface structure for delivery of respiratory therapy to apatient according to an example embodiment of the present technologycomprises a front plate configured to conform to the shape of thepatient's face; a mouth cushion defining a breathing chamber andprovided to the front plate and configured to seal around the patient'smouth; and a nasal cushion configured to seal the patient's nasalairways, wherein the nasal cushion is supported by the mouth cushion,does not contact a bridge of the patient's nose in use, and extend atleast partially into the breathing chamber.

A patient interface structure for delivery of respiratory therapy to apatient according to an example embodiment of the present technologycomprises a front plate configured to conform to the shape of thepatient's face; a mouth cushion defining a breathing chamber andprovided to the front plate and configured to seal around the patient'smouth; and a nasal cushion configured to seal the patient's nasalairways, wherein the nasal cushion is supported by the mouth cushion,does not contact a bridge of the patient's nose in use, and is raisedabove the breathing chamber.

A patient interface system according to an example embodiment of thepresent technology comprises a patient interface structure according tothe present technology and a patient interface structure positioningsystem configured to position, stabilize and secure the patientinterface structure in sealing engagement with the patient's face.

A patient interface system according to an example embodiment of thepresent technology comprises a cushion adapted to sealingly engage witha patient's airways, the cushion comprising a slot adapted to receive aheadgear connecting portion of a fascia.

Other aspects, features, and advantages of this technology will becomeapparent from the following detailed description when taken inconjunction with the accompanying drawings, which are a part of thisdisclosure and which illustrate, by way of example, principles of thistechnology.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings facilitate an understanding of the variousembodiments of this technology. In such drawings, in which likereference symbols indicate like features:

FIGS. 1-6 are front isometric, front, rear, left, right, and bottomviews, respectively, of an example embodiment of a patient interfacesystem according to the present technology;

FIGS. 7-13 are front isometric, front, rear, top, bottom, right and leftside views, respectively, of a fascia, or front plate, of the patientinterface system of FIGS. 1-6;

FIGS. 14-19 are front isometric, front, left side, right side, rear andbottom views, respectively, of a patient interface system according toanother example embodiment of the present technology;

FIGS. 20-25 are front, rear, rear isometric, top, bottom, and left sideviews, respectively, of a fascia, frame or front plate, of the patientinterface system of FIGS. 14-19;

FIG. 26 is a front isometric view of a patient interface according toanother example embodiment of the present technology and FIGS. 27-33 arefront isometric, front, rear, right side, left side, top, and bottomviews, respectively, of a fascia, frame or front plate, of the patientinterface system of FIG. 26;

FIGS. 34-40 are front isometric, front, rear, left side, right side,top, and bottom views, respectively, of a patient interface systemaccording to another example embodiment of the present technology;

FIGS. 41-47 are front isometric, front, rear, left side, right side,top, and bottom views, respectively, of the fascia, frame or frontplate, including an elbow and the patient interface positioning systemof the patient interface system of FIGS. 34-40;

FIG. 48 is a front isometric view of the fascia, or front plate,including the elbow, and the seal (e.g. cushion) of the patientinterface system of FIGS. 34-30;

FIGS. 49-55 are front isometric, front, rear, right side, left side,top, and bottom views, respectively, of the fascia, frame or frontplate, including the elbow, of the patient interface system of FIGS.34-40;

FIGS. 56-62 are front isometric, front, rear, rear isometric, rightside, top, and bottom views, respectively, of a patient interfacepositioning system according to an example embodiment of the presenttechnology;

FIGS. 63-69 are front isometric, front, rear, top, bottom, right side,and left side views, respectively, of a mouth seal, or cushion,according to an example embodiment of the present technology;

FIGS. 70-76 are front/bottom isometric, front, rear, top, bottom, side,and front/top isometric views, respectively, of a nasal seal, orcushion, according to an example embodiment of the present technology;

FIGS. 77-83 are front isometric, front, rear isometric, rear, rightside, top, and bottom views, respectively, of a seal, or cushion,including the mouth and nasal seals, or cushions, of FIGS. 63-69 and70-76, respectively, according to an example embodiment of the presenttechnology;

FIG. 84 is a front view of a patient interface system according toanother example embodiment of the present technology;

FIG. 85 is a front view of a patient interface system according toanother example embodiment of the present technology;

FIG. 86 is a front isometric view of a patient interface systemaccording to another example embodiment of the present technology;

FIG. 87 is a rear view of a patient interface system according toanother example embodiment of the present technology;

FIGS. 88-94 are views of a patient interface system according to anotherexample embodiment of the present technology;

FIG. 95 is a front isometric view of a patient interface systemaccording to another example embodiment of the present technology;

FIG. 96 is a front view of a patient interface system according toanother example embodiment of the present technology;

FIG. 97 is a front view of a patient interface system according toanother example embodiment of the present technology;

FIG. 98 is a front view of a patient interface system according toanother example embodiment of the present technology;

FIG. 99 is a front view of a patient interface system according toanother example embodiment of the present technology;

FIG. 100 is a front view of a patient interface system according toanother example embodiment of the present technology;

FIG. 101 is a front isometric view of a patient interface systemaccording to another example embodiment of the present technology;

FIG. 102 is an exploded assembly view of a patient interface systemaccording to another example embodiment of the present technology;

FIG. 103 is a front isometric view of a patient interface systemaccording to another example embodiment of the present technology;

FIG. 104 is a rear view of a mouth seal, or cushion, according to anexample embodiment of the present technology;

FIG. 105 is a left side view of the mouth seal, or cushion, of FIG. 104;

FIG. 106 is a schematic illustration of a fascia, or front plate, and aseal, or cushion, including an anti-asphyxia valve according to anexample embodiment of the present technology;

FIG. 107 is a schematic illustration of a fascia, or front plate, and aseal, or cushion, including an anti-asphyxia valve according to anotherexample embodiment of the present technology;

FIG. 108 is a schematic illustration of a fascia, or front plate, and aseal, or cushion, including a gusseted side wall according to an exampleembodiment of the present technology;

FIG. 109 is a schematic illustration of a strap, for example a rearstrap, of a patient interface positioning system (e.g. headgear)according to an example embodiment of the present technology;

FIG. 110 is schematic illustration of the strap of FIG. 109 connected toa delivery tube or conduit or hose;

FIG. 111 is a schematic illustration of a strap, for example a rearstrap, of a patient interface positioning system (e.g. headgear)according to another example embodiment of the present technology;

FIG. 112 is a schematic illustration of a strap, for example a rearstrap, of a patient interface positioning system (e.g. headgear)according to another example embodiment of the present technology;

FIG. 113 is a schematic illustration of a fascia, or front plate,including a venting arrangement according to an example embodiment ofthe present technology;

FIG. 114 is a schematic illustration of a patient interface systemrotatably connectable to a patient interface positioning systemaccording to an example embodiment of the present technology;

FIG. 115 is a rear view of a cushion assembly, including a mouth seal orcushion and a nasal seal or cushion;

FIG. 116 is a front view of the cushion assembly of FIG. 115 including acushion clip;

FIG. 117 is a cross section view of the cushion assembly and cushionclip along line 117-117 in FIG. 116;

FIG. 118 is a detailed view of the connection of the cushion assemblyand the cushion clip at a lower portion of the cushion assembly;

FIG. 119 is a detailed view of FIG. 118;

FIG. 120 is a detailed view of the connection of the cushion assemblyand the cushion clip at an upper portion of the cushion assembly;

FIG. 121 is a detailed view of FIG. 120;

FIG. 122 is a top view of the cushion assembly and cushion clip;

FIG. 123 is a rear view of the cushion clip;

FIG. 124 is a front view of the cushion clip;

FIG. 125 is a cross section view of the cushion clip along line 125-125in FIG. 124;

FIG. 126 is a left side view of the cushion clip;

FIG. 127 is a detailed view of FIG. 125;

FIG. 128 is a top view of the cushion clip;

FIG. 129 is a rear isometric view of a cushion assembly according to anembodiment of the present technology;

FIG. 130 is a rear view of the cushion assembly of FIG. 129;

FIG. 131 is a cross section view of the cushion assembly along line131-131 in FIG. 130;

FIG. 132 is a rear isometric view of a cushion according to anembodiment of the present technology;

FIG. 133 is a rear view of the cushion assembly of FIG. 132;

FIG. 134 is a cross section view of the cushion assembly along line134-134 in FIG. 133;

FIG. 135 is a front isometric view of the cushion assembly and cushionclip of FIG. 125; and

FIG. 136 is a left side view of the cushion assembly and cushion clip ofFIG. 135.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

The following description is provided in relation to several embodimentswhich may share common characteristics and features. It is to beunderstood that one or more features of any one embodiment may becombinable with one or more features of the other embodiments. Inaddition, any single feature or combination of features in any of theembodiments may constitute additional embodiments.

In this specification, the word “comprising” is to be understood in its“open” sense, that is, in the sense of “including”, and thus not limitedto its “closed” sense, that is the sense of “consisting only of”. Acorresponding meaning is to be attributed to the corresponding words“comprise”, “comprised” and “comprises” where they appear.

The term “air” will be taken to include breathable gases, for exampleair with supplemental oxygen. It is also acknowledged that the blowersdescribed herein may be designed to pump fluids other than air.

Patient Interface Systems

Referring to FIGS. 1-13 and 56-62, a patient interface system or masksystem 10 in accordance with an example embodiment of the presenttechnology comprises a patient interface structure or mask structure 20that is positioned, stabilized and secured on a patient's head insealing engagement with the patient's mouth and nasal airways by apatient interface positioning system 30, e.g. a headgear. The patientinterface structure 20 comprises a fascia or lens or front plate orframe 21 having a mouth seal, or cushion 23 that is connected to thefront plate 21. The front plate 21 includes patient interfacepositioning system connectors 22 (e.g. headgear connectors) to connectthe patient interface positioning system (e.g. headgear) 30 to thepatient interface structure (e.g. mask) 20. The patient interfacestructure further comprises a nasal seal, or cushion 24 connected to themouth seal, or cushion 23 to seal the patient's nasal airways. A vent 25may be provided in the front plate 21 to vent exhaled gases in abreathing chamber defined by the front plate 21, the mouth cushion 23and the nasal cushion 24. The vents may be provided in the front plate21 proximate the nares and/or mouth of the patient to improve CO.sub.2washout. The array of vent holes 25 may be laser cut, molded orotherwise formed in an upper region of front plate 21.

Patient Interface Positioning System

The patient interface positioning system 30 comprises a crown strap 31adapted to cup or encircle the crown of the patient's head. Top, orupper side straps 32 extend from the crown strap 31 and connect to thefront plate 21 through slots 27. The ends 33 of the top side straps 32may be looped through the slots 27 and connect to the top side straps 32by, for example, hook and loop material. It should also be appreciatedthat other connections, for example buckles, may be used to secure theends 33 of the top side straps 32. The top side straps 32 may bethickened or widened at the region where they connect to the crown strap31 to allow ends 33 a larger space to connect to and also a range ofangles to position ends 33 relative to slows 27, thereby improving thefit range of the headgear 30. Such an arrangement may also improvecomfort and/or to assist in stabilizing and positioning the top sidestraps 32 on the patient's cheek bone regions.

The crown strap 31 may further comprise a loop 40 through which a rightbottom, or lower side strap 35 may pass and connect to a left bottom, orlower side strap 34. It should also be appreciated that the loop may beformed in the lower strap(s) 34 and/or 35, for example as shown in U.S.Applications 61/443,623 and 61/457,981, each of which is incorporated byreference herein in its entirety. It should further be appreciated thatother headgear may be used with the patient interface system, forexample as disclosed in U.S. Patent Application Publication 2008/0110466A1, the entire contents of which are incorporated herein by reference.The bottom right side strap 35 may comprise a first end 38 in the formof a loop or slot and a first end 36 of the bottom left side strap 34may connect to the first end 38 by passing through the loop or slot andconnecting through hook and loop material or buckles or otherconnectors. The second end 37 of the bottom left side strap 34 and thesecond end 39 of the bottom right side strap 35 may be connected to thefront plate 21 through slots 26 in the connectors 22.

Headgear 30 may be formed from a composite e.g. fabric and foam, whichmay be flame laminated and may be ultrasonically die cut or welded alongits edge to create a rounded, more comfortable edge.

Front Plate/Fascia/Lens

The front plate 21 is configured to conform to or accommodate the shapeof the patient's face. The front plate 21 may be flexible to allow thefront plate to follow the shape of the patient's face. The front plate21 may be formed of, for example, a flexible polymer that is able tobend and conform around the patient's mouth once the front plate 21 isconnected to the patient interface positioning system 30 and fitted tothe patient. The front plate 21 may also be malleable to allow the frontplate to conform to the shape of the patient's face. A rib(s) 28 may beprovided to the front plate 21. The ribs 28 may be provided along thetop and bottom of the front plate 21 and aid in alignment and engagementwith the cushion 23, as well as providing strength to the fascia.

Front plate 21 may be substantially planar, curved and/or smooth. Masksknown in the art tend to include complex shapes and/or structures on theframe, and these complex shapes and/or structures make it difficult tosee the patient's mouth clearly and to clean the frame. For example,these complex shapes and/or structures may include elbows, elbowconnectors, ports, ridges, contours, headgear connectors, etc. Frontplate 21 is adapted to be substantially smooth and without complexshapes or structures i.e. having a substantially planar surface in theregion of the patient's mouth, to act as a window to permit clearvisibility to the patient's mouth.

As shown on FIGS. 14 and 15, the patient interface structure 20 may begenerally rectangularly or trapezoidally shaped and comprise the frontpanel 21 that wraps across the face of the patient 1, and the cushion23, 24 attached to the front plate 21. The cushion 23 may comprise theintegrated mouth seal or cushion 23 and the nasal seal or cushion 24.The front plate 21 may be generally convex when viewed from thenon-patient contacting side, curved or rounded shaped and adapted tofollow the contour of the patient's face. The bottom side strapconnector slots 26 and the top side strap connector slots 27 of theconnectors 22 on either side of the front plate 21 may receive theheadgear straps 32, 34, 35 and the tension or force from the headgearstraps 32, 34, 35 may bend or flex the front plate 21 to conform to theshape of the patient's face. The top side strap connector slots 27 aredirected generally upwards and are adapted to aid sealing of the nasalcushion 24 and direct the headgear away from the patient's eyes 4, andthe bottom side strap connector slots 26 are adapted to aid sealing ofthe mouth cushion 23 and direct the headgear straps 34, 35 under theears 2 of the patient 1.

The fascia or lens or front plate 21 is positioned in front of thepatient's mouth, and is adapted to provide support to the othercomponents of the patient interface system 10 and aid in positioningthese other components, for example the front plate has headgearconnectors 22 and a cushion connection portion adapted to receive thepatient interface positioning system 30 and a cushion 23 and positionthese components relative to one another. The front plate 21 alsoprovides some structure to the patient interface system 10 due to thecomparatively greater rigidity of the front plate 21 when compared tothe cushion 23.

The front plate 21 may take the form of a lens made from a clearmaterial such as nylon, polycarbonate or nearly clear material such aspolypropylene. The lens may be shaded, selectively shaded (e.g.gradient, patterned, random assortment of shapes), printed on orotherwise coloured. The lens may also have colour changing propertiese.g. it may be clear when the light is on, and may be opaque when thelight it off. The lens may also be customizable. The lens may beprovided with a skin or adhesive layer that may customize or otherwisealter the lens. The lens may be surface treated e.g. frosted. The lensmay be die cut, drape formed, vacuum formed, molded, cast,ultrasonically cut or formed in any other method to create the desiredshape. The lens may also be formed with vent holes. The vent holes maybe molded in, laser cut or otherwise formed with the lens. The lens maybe flexible or capable of being shaped to fit the patient's face.

Cushion/Seal

Referring to FIGS. 63-83, the cushion or seal of the patient interfacesystem may comprise two components the mouth cushion or seal 23 and thenasal cushion or seal 24. The cushions 23, 24 may be molded together orotherwise permanently attached (e.g. glue, weld). The mouth cushion 23provides the mouth sealing portion and also the support for the nasalcushion 24. The mouth cushion 23 also connects to the front plate 21.The nasal cushion 24 is a nares sealing portion that may be molded fromthe same or alternative material to mouth cushion 23. Separating thecushion into two components allows use of a lower durometer (i.e. lowerhardness) material for the nasal seal or cushion 24, and the toolingrequired to mold the nasal seal or cushion 24 with the mouth seal orcushion 24 is difficult, so molding them in two steps rather than onefacilitates manufacturing.

The cushions 23, 24 may be made from a single material such as silicone,TPE, TPU. However, combinations of materials and/or hardnesses ofmaterials may be used. For example, the mouth seal or cushion 23 mayhave a TPE or silicone body, with a seal portion or flap adapted tointerface with the patient. The nasal seal 24 may comprise a sealportion formed of an alternative material, for example a lower hardnesssilicone, TPU, fabric, etc.

Referring to FIGS. 63-69, the mouth cushion 23 comprises a groove orchannel 231 around a front portion 238 that is adapted to receive thefront plate 21. The channel 231 may have a flap 232 around the innerside of the channel that is adapted to seal against the face of thepatient around the patient's mouth. The flap 232 may comprise a singlewall seal, although it should be appreciated that the flap 232 maycomprise more than one wall, for example two or three walls. The mouthcushion 23 may be constructed from a deformable material such as TPE,TPU, silicone, foam (skinned or unskinned), or gel.

It should be appreciated that the mouth cushion 23 may be insert, over,or co-moulded to the front plate 21. It should be further appreciatedthat a cushion clip may be provided to the cushion to clip to the frontplate 21. The clip may be insert, over, or co-moulded into the cushion23 as one part. The cushion clip may add stiffness and rigidity to thecushion 23 where required, provide patient interaction points, and allowfor a locating and attaching method of the cushion 23 to the front plate21, e.g. the cushion clip may snap onto the front plate 21. The cushionclip may simplify the process of attaching the cushion 23 to the frontplate 21 by reducing stretching and warping of the cushion 23 duringassembly.

Slots 234 are provided in side walls 233 of the cushion 23 and areadapted to receive the connectors 22 of the front plate 21. Slots 234may be generally rectangular, however any other shape may be possible,such that slots 234 may be complimentary to the shape of connectors 22.Connectors 22 may sealingly engage with side walls 233, for example sidewalls 233 may comprise a lip seal or other arrangement adapted to sealagainst connectors 22.

The upper portion 237 of the mouth seal or cushion 23 has a greaterdepth when compared with the lower portion 239 of the mouth seal orcushion 23, i.e. the distance of the seal portion to the clip portion ofthe upper portion may be longer than the distance from the seal portionto the clip portion of the lower portion, to tilt the cushion 23 when inuse to reduce the profile of the mask 20 when in use. The upper portion237 of the mouth seal or cushion 23 may also have a greater depth thanthe lower portion 239 to accommodate nasal seal or cushion 24 andpatients with long noses.

Flaps 252 are provided on nares support portions 235 to assist inpositioning and stabilizing the nasal seal or cushion 24 to engage withthe sides of the patient's nose or the patient's top lip. Raisedportions 253 on the nares support portion 235 aid in positioning thenasal seal 24 against the flares of the patient's nostrils. Indents orapertures 254 are formed in the nasal support portions 235 and areadapted to receive lugs 241 on nasal seal or cushion 24 to aid inalignment.

A channel 251 may be provided around the nares support portions 235 toform a flexible region (e.g. could be localized thinning of material)adapted to permit movement of the nasal seal or cushion 24 toaccommodate varying anthropometrics.

The side walls 233 of the mouth seal or cushion 23 may have a “questionmark” cross section, i.e. the mouth seal portion does not have astraight wall section but rather has a gusseted side wall that acts as abuilt-in spring so that the mouth seal portion can flex to fit varyingpatient anthropometrics. Such a side wall cross section is disclosed in,for example, U.S. Patent Application Publication 2008/0110464 A1, theentire contents of which are incorporated herein by reference.

The front portion 238, the side walls 233 and the flap 232 of the mouthcushion 23 may have different hardnesses. For example, the front portion238 may have a Shore A durometer of about 30-50, for example about 40.The side walls 233 and/or the flap 232 may have a Shore A durometer of5-10, for example about 7.

Referring to FIGS. 104 and 105, the cushion or seal may be formed of afoam, gel, or low durometer material to seal with the patient. Twogusset or spring portions 288, 289 may be formed behind the seal portionto aid in adjustment of the positioned of the seal portion. The corner287 of the nose region may be raised to ensure the seal abuts thepatient's face and seals in this region.

Referring to FIG. 108, a gusset type arrangement may be provided topermit flexibility of the cushion and aid sealing under air pressure,with the seal portion 232 turning outwards. This arrangement mayincrease the fit range.

Referring to FIGS. 70-76, the nasal seal or cushion 24 may comprise lugs241 adapted to be received in indents 254 of the nare support portions235 of the mouth seal or cushion 23. The nasal seal or cushion 24 mayhave a geometry the same as or similar to that disclosed in, forexample, WO 2010/139014 A1, the entire contents of which areincorporated herein by reference. The nare support portions 235 and thecradle wall 236 form a trampoline type join with the nasal seal orcushion 24. The nasal seal or cushion 24 may have a Shore A durometer ofabout 30-50, for example about 40. The nasal seal or cushion 24 may havea Shore A durometer of about 5-10, for example about 7.

Referring to FIGS. 77-83, in the assembled condition, the flaps 252 ofthe nares support portions 235 of the mouth seal or cushion 23 attach tothe respective sides of the nasal seal or cushion 24. A central portion242 of the nasal seal or cushion 24 is left unsupported by the naressupport portions 235 to allow the flexibility of the central portion 242accommodate varying shaped lip regions of patients. As shown in FIG. 78,the top portion 238 of the mouth seal or cushion 23 is generally in linewith or vertically aligned to the nasal seal or cushion 24 so thepatient's nose is likely to rest inside the cushion. The nasal seal orcushion 24 is positioned to reside within the mouth cushion 23 whichreduces visual bulk and streamlines the outer edge of the mask. As shownin FIG. 79, the slots 234 for the connectors 22 of the front plate 21are positioned below the nasal seal 24 so as to direct the headgearstraps 34, 35 along or below the patient's cheeks. It should beappreciated that the patient interface system may comprise a number ofnasal seals or cushions 24. For example, a single mouth cushion 23 maybe provided to fit a large percentage of the patient population and twoor more nasal seals or cushions 24 may be provided to provide a morecustom fit for individual patients nose sizes.

Referring to FIG. 96, it should be appreciated that a nasal seal orcushion comprising nasal pillows may be provided to the mouth cushion.It should be appreciated that a plurality of nasal seals or cushionshaving different size nasal pillows may be provided to the patientinterface system.

Referring to FIG. 97, the tube connector may comprise an elbow 269 thatis rotatably connected to the front plate 21. Elbow 269 may be lockablein the two positions as show, i.e. left and right horizontalorientations.

Referring to FIG. 98, the patient interface structure 20 may include ananti-asphyxia valve 270 provided in the front plate 21.

Referring to FIG. 99, the front plate 21 may include a receptacle 270configured to receive a clip 271 provided on a strap 35 of the patientinterface positioning system. As shown in FIG. 100, the front plate 21may include receptacles 270 on opposing sides, each configured toreceive a clip 271 attached to a strap 34, 35. The clips and receptaclesmay also be magnetic.

Cushion/Seal—Cushion Clip

Referring to FIGS. 115-128, 135 and 136, a seal or cushion assemblyincludes a mouth seal or cushion 23 and a nasal seal or cushion 24. Thecushion assembly may be similar to that disclosed with respect to FIGS.63-83 except as otherwise described herein. The cushion assembly maycomprise a cushion clip 400 attached to the cushion assembly andconfigured to attach the cushion assembly to a fascia or front plate orlens as described herein. The cushion clip 400 may comprise detents 402on opposite sides to retain the cushion assembly on the fascia. As shownin, for example, FIG. 128, the cushion clip 400 may have a curvedportion 401 that curves away from the cushion assembly to allow thenasal seal 24 to have a greater depth than a top surface of the mouthcushion 23. This may allow the nasal seal 24 to accommodate long noses.As shown in FIG. 116, the central portion 242 of the mouth cushion 23may dip or curve downwards towards the patient's lip to avoid contactingthe patient's septum. As shown on FIG. 115, nasal seal 24 may compriseraised upper corner regions, these raised upper corner regions adaptedto engage a patient's nostrils or nasal flares, thereby reducing theforce on the patient's nose tip.

Referring to FIG. 115, the height of the aperture in the mouth cushionmay be about 25-35 mm. Preferably, the height of the aperture on themouth cushion may be about 25-30 mm. The height is measured from thelowest portion of the opening at the chin region to the dip or curve ofthe opening at the top lip region. The height of the aperture mayincrease towards the cheek or left and ride side regions.

Referring to FIG. 122, the height of the aperture in the nose cushionmay be about 5-15 mm. Preferably, the height of the aperture in the nosecushion may be about 7-12 mm. The height of the aperture in the nosecushion may be less in the central region of the aperture compared tothe height of the aperture at the side regions. That is, the nosecushion aperture may have a dip or curved portion at the central region.Such an arrangement may aid in alignment of the cushion, avoid placingexcess pressure on the patient's septum and/or ensure that the lowerportion of the nasal cushion is not under tension and therefore may notexert pressure on the patient's top lip.

Referring to FIG. 115, the width of the aperture in the mouth cushionmay be about 60-70 mm. Preferably the width of the aperture in the mouthcushion may be about 63-68 mm. Such a width may accommodate varyingmouth widths of patient's.

Referring to FIG. 122, the total width of the nose and mouth cushion maybe about 90-105 mm. Preferably, the total width of the nose and mouthcushion may be about 95-100 mm. Such a width may accommodate varyingpatient anthropometrics.

Referring to FIG. 115, the total height of the nose and mouth cushionmay be about 60-75 mm. Preferably, the total height of the nose andmouth cushion may be about 65-75 mm. Such a height may accommodatevarying patient anthropometrics.

The patient contacting portion of the nose and/or mouth cushions may beabout 0.3-1.5 mm thick. Preferably, patient contacting portion of thenose and/or mouth cushions may be about 0.3-0.7 mm thick. Such athickness may ensure conformability of the cushion and comfort for thepatient.

Referring to FIG. 116, the height of the clip may be about 40-55 mm.Preferably, the height of the clip may be about 45-55 mm. The height ofthe clip may be greater than the height of the mouth cushion aperture.Such an arrangement may be simpler to engage the clip with a fascia (forexample) and may increase the structural integrity of the cushion.

Referring to FIG. 116, the width of the clip may be about 70-85 mm.Preferably, the width of the clip may be about 75-80 mm. The width ofthe clip may be greater than the width of the mouth cushion aperture.Such an arrangement may be simpler to engage the clip with a fascia (forexample) and may increase the structural integrity of the cushion.

As shown in, for example, FIG. 124, the cushion clip may be generallytrapezoidal, with the top portion being wider than the lower portion.Such an arrangement may mean that the overall shape of the mask isshaped to match the general shape of a humans face i.e. taper from agreater width at the top lip region to a lower width at the chin region.The top portion may be, for example, about 75-85 mm wide. The lowerportion may be, for example, about 65-75 mm wide.

As shown in, for example, FIGS. 117-121, the cushion may be integrallyformed in one piece. The mouth cushion 23 may have a single wall 232 andthe nasal cushion 24 may have a dual wall construction comprising asealing wall 243 and a supporting wall 244. It should be appreciatedthat the mouth cushion 23 and the nasal cushion 24 may each include asingle wall, or each may include multiple walls. The sealing walls 232and 243 of the mouth cushion 23 and the nasal cushion 24 may curveinwards toward a breathing chamber or cavity formed by the cushions. Asshown in FIG. 117, only a portion of the supporting wall 244 of thenasal cushion 24 may be present, for example, at the tip of the noseregion and not at the top of the lip region. Referring to FIG. 122, aparting line 245 of the mould used to form the cushion assembly may beprovided so as to be above the patient contacting areas of the cushionassembly.

Referring to FIG. 136, the cushion assembly and the cushion clip 400 maybe formed integrally in one piece. The cushion assembly may be insert,over, or co-moulded into the cushion 23 as one part. Alternatively, thecushion assembly and the cushion clip 400 may be chemically ormechanically bonded together. The cushion assembly and cushion clip 400may also be repeatably attachable and detachable from one another. Forexample, the cushion clip 400 may include a flange configured to bereceived in a channel in the cushion assembly.

As shown in FIGS. 117-121, 126 and 127, the cushion clip 400 may includea flange or rib 403 to increase the surface area of the cushion clip 400to enhance the bond between the cushion clip 400 and the cushionassembly. The cushion assembly, for example the mouth cushion 23, mayinclude a thickened region 310 to provide support for the seal wall 232and to improve the bond to the cushion clip 400. Rib 403 may have avarying height around the perimeter of the cushion clip 400. Thisvarying height may support the cushion more in some regions (i.e. theregions with a greater rib height such as sensitive regions of the facesuch as the top lip) compared to support in other regions (i.e. regionswith a lower rib height such as less sensitive regions of the face suchas the cheeks).

Cushion Assembly—Continuous Sealing Surface

Referring to FIGS. 129-131, a cushion assembly including a mouth cushion23 and a nasal cushion 24 may comprise a continuous sealing surface 246.As show in FIG. 131, the sealing surface 246 is continuous with themouth cushion sealing wall 232 and the nasal cushion sealing wall 243.The curvature of the sealing surface 246 may be constant orapproximately constant. Such an arrangement may be comfortable for thepatient as there are no ridges or undulations that may mark or otherwiseirritate the patient's skin. In this arrangement, the definition betweenthe nose and mouth seal portions is not distinct, such that the seal iscontinuous.

Cushion Assembly—Separate Sealing Surfaces

Referring to FIGS. 132-134, a cushion assembly including a mouth cushion23 and a nasal cushion 24 includes separate sealing surfaces 247, 248. Achannel 249 is provided to separate the nasal sealing surface 247 fromthe mouth sealing surface 248. Such an arrangement may be preferable asthe nose and mouth seal portions are visually distinct which may assistthe patient with aligning the device.

Patient Interface Systems—Tube Connection—Behind Connector

Referring to FIGS. 14-25, a patient interface system 10 according to anexample embodiment of the present technology includes a delivery hose,or tube, or conduit 11 that is connected to the front panel 21 by aconnector 12, e.g. a swivel connector. The tube 11 may be as disclosedin, for example, U.S. Patent Application Publication 2009/0078259 A1,the entire contents of which are incorporated herein by reference. Thefront panel includes an air inlet or elbow 29 that may be integrallyformed with the front plate 21. It should be appreciated that the elbow29 may be formed separately from the front plate 21 and attached orconnected to the front plate 21 or the cushion 23, for example byadhesive or mechanical fasteners. The elbow 29 is positioned behind oradjacent to the connector 22 of the front plate 21 on the left side,although it should be appreciated that the elbow 29 may be provided onthe right side of the front plate 21. The shape of the elbow 29 iscurved to avoid obscuring the headgear connector 22. However otherconfigurations would be possible if the headgear connector 22 waslocated in an alternative position.

The tube connection portion of the elbow 29 is adapted to receive thetube 11 in a longitudinal (e.g. vertical) direction, however otherorientations are possible. The elbow 29 is not visible from the front asit is hidden behind the headgear connector 22 of the front plate 21.This arrangement is advantageous as it is reduces the part count (i.e.no separate elbow is required) and the design may be more visuallyappealing. The tube 11 is connected at the side of the patient interfaceor mask system 10 so as to permit clear view to the patient's mouth.Because the tube connection is positioned behind the headgear connector22 at the front plate 21, the tube 11 is less obtrusive. The eyes 4 ofthe patient 1 are unobstructed and in the case of the front plate 21being in the form of a lens, for example a clear polymer (e.g.polycarbonate), the patient's mouth would also be visible.

The elbow 29 may comprise a lip or protruding edge 41, in the form offor example a chamfer, adapted to receive a slot or aperture of thecushion. The cushion 23 may comprise a slot that may be positioned toabut or align with the chamfer to aid alignment, and also ensure an airtight seal between the cushion 23 and the front plate 21 is achieved.

The patient interface structure 20 sits under the patient's nose 3 andthe nasal cushion 24 seals around or in the nares. The mouth cushion 23sits in the crease of the patient's chin 5. The crown strap 31 of theheadgear 30 is positioned over the top of the patient's crown andgenerally in line with the patient's ears 2, although it should beappreciated that the positioning of the crown strap 31 may vary betweenpatients.

Although the front plate 21 shown in FIGS. 20-25 includes only thebottom side strap connector slots 26, it should be appreciated that theembodiment shown in FIGS. 20-25 may also comprise top sides strapconnector slots 27. It should also be appreciated that the front plate21 may be provided with a vent, or alternatively another component, suchas the tube 11, the connector 12, or the elbow 29 may have a vent.

Referring to FIG. 101, a tube connector 272 may be positioned either onthe front plate 21 or molded with the cushion 23. The tube connector 272may receive an intermediate portion or portion 274 of a tube 273 thatmay interface with the tube connector 272 by an interference fit. Theinterference fit may be achieved by pinching or otherwise misshaping theintermediate portion or portion 274 of the tube 273 and placing itwithin the tube connector 272. When the pinch or other force isreleased, the intermediate portion or portion 274 of the tube 273 mayresiliently flex back to its original shape and interface with an innersurface of the tube connector 272. In an alternative arrangement, tube273 that may interface with the tube connector 272 by an interferencefit such as an isometric taper or a quarter turn lock.

Patient Interface Systems—Tube Connection—Front Surface

Referring to FIGS. 26-33, a patient interface system 10 according toanother example embodiment of the present technology comprises a patientinterface structure 20 comprising a front plate 21, a mouth cushion 23provided to the front plate 21, and a nasal cushion 24 provided to themouth cushion 23. The front plate 21 comprises a tube connector 42 on afront surface that is configured to receive a tube in a horizontaldirection.

A tube may connect directly to the tube connector 42 or may have anintermediate structure such as an elbow or swivel between the tube andthe tube connector 42, possibly shaped to avoid the tube obscuring theheadgear connector 22. The tube connector 42 may have vent holes 25molded or otherwise formed in it. The tube connector 42 may also have alip or protruding edge 43, which may aid in sealing the tube connector42 to the tube or intermediate structure. The tube connector 42 may havean anti-asphyxia valve (AAV) in form of a flap built in (described inmore detail below) that may occlude or block some of the vent holes 25when air is delivered from the tube and through the tube connector 42.When air pressure is not supplied, the AAV may flip away from the ventholes to permit the patient to breath in sufficient atmospheric air.

The rear face of the front plate 21 may have an aperture 44 adapted topermit the flow of air from the tube connector into the mask. The vents25 may have a thicker cross section than the rest of the tube connector42 (e.g. they are on a raised rectangular portion) to improvemanufacturability. This may also be to increase the length of the ventholes 25 as longer vent holes are typically quieter than comparativelyshorter vent holes. The tube connector 42 may follow the same generalcurvature of the front plate to reduce the visual bulk (i.e. morestreamlined look) of the mask and aid in tube management.

Patient Interface Systems—Tube Connection—Elbow

Referring to FIGS. 34-55, a patient interface system 10 according toanother example embodiment of the present technology may comprise anelbow 45 connected substantially perpendicular to the front plate 21.The elbow 45 may be a swivel elbow or may be a ball joint elbow. Theelbow 45 may be removably attachable or molded with the front plate 21.

Patient Interface Systems—Vents

Referring to FIG. 84, a patient interface system 10 may comprise a frontplate 21 having a vent 25 comprising a plurality of vent holes providedaround a perimeter of the front plate 21. The perimeter arrangement aidsdiffusivity of the exhaust gases and reduces the visibility of the vent25.

Referring to FIG. 85, a patient interface system 10 may comprise a frontplate 21 having a vent 25 that comprises micro-perforated holes over thefront surface of the front plate 21.

Referring to FIG. 113, a tortuous vent path through front plate 21 maybe provided for reducing noise. The tortuous path will slow down theexhaled gases 296 as it moves through the tortuous path, thereby havinga lower sound power. The mouth seal may have an interface seal 293 and aflap or castellation 294 that obstructs the vent holes 25, with theexhaled gases 296 moving through the vented pathway 295 of a raisedportion 292 of the front plate 21 rather than directly out of the ventholes 25 to increase the length of the path for exhaled gases to get outof the mask.

Patient Interface Systems—Tube Cuff

Referring to FIG. 86, a patient interface system 10 may include a mouthcushion 23 having a tube cuff 255 attached to, for example, the sidewall 233 of the cushion 23. The tube cuff 255 may be moulded onto theside wall 233 and may have a hardness greater than that of the side wall233.

Referring to FIG. 95, a tube cuff 268 may be moulded onto the cushion 23that is configured to be connected to a connector 12, e.g. a swivelconnector, that is configured to be connected to a tube 11, for examplea tube as disclosed in U.S. Patent Application Publication 2009/0078259A1, the entire contents of which are incorporated herein by reference.It should be appreciated that the tube cuff 268 may be connected to thecushion by, for example, adhesive or mechanical connectors.

Referring to FIG. 103, a gap 286 between a tube connector 283 and a cuff284 (having less width when compared to the tube connector for example)may be adapted to receive a headgear strap that extends in asubstantially vertical direction. The cuff 284 may include a link orslot 285 to receive a headgear strap that extends in a substantiallyhorizontal direction. The cuff 284 may be soft or relatively flexible.The cuff 284 may be glued on or otherwise attached to the tube connector283. The cuff 284 may be formed with the tube connector 283.

Patient Interface Systems—Anti-Asphyxia Valves (AAV)

Referring to FIG. 87, a patient interface system 10 may comprise a frontplate or lens 21 having a hole 256. An anti-asphyxia valve in the formof a flap 257 formed in the mouth seal or cushion 23 is forced againstthe front plate 21 and covers the hole 256 when a flow of pressurizedgas is delivered through a tube or hose or conduit 258. In the absenceof the flow, the flap 257 is released from contact with the front plate21 and uncovers the hole 256, allowing the patient to breathe ambientair through the hole 256 in the front plate 21.

Referring to FIGS. 88-95, a patient interface system 10 may comprise afront plate 21 having a tube connector 42 configured for connection witha tube or hose or conduit 259. The tube connector 42 comprises anaperture or window 264 that may be closed by an anti-asphyxia valve 260.The anti-asphyxia valve 260 comprises a flap 261 that is configured toopen and close the aperture 264. The flap 261 may comprise a vent 25 forventing exhalation gases when the flap 261 closes the aperture 264. Theanti-asphyxia valve further includes a tab 262 that secures theanti-asphyxia valve 260 in the tube connector 42 through a slot 265 inthe tube connector 42. The flap 261 is pivotably connected to the tab262 by a hinge 263, e.g. a living hinge. As shown in FIG. 94, in theabsence of a flow of gas in the tube connector 42, the flap 261 extendsacross the tube connector, and the patient may breathe through theaperture 264. When gas flow 266 is delivered to the tube connector 42,the pressure of the gas flow 266 pivots the flap 261 in the directionshown by arrow 267 to close the aperture 264. Exhalation gases may bevented through the vent 25. Referring to FIG. 92, the flap 261 mayinclude elongated vent holes 25 to reduce venting noise and increasediffusivity of the vent flow.

Referring to FIGS. 106 and 107, the cushion may have a flap or thinportion 290 around its perimeter that interfaces or otherwise abuts thefront plate. The flap may be pressure activated i.e. when air isdelivered under pressure into the mask, the flap may be forced to abutthe front plate causing an air tight seal. If air is no longer deliveredto the mask, the flap may relax and permit air from atmosphere into themask via a gap 290 created between the flap and the front plate.

Patient Interface Systems—Materials

Referring to FIG. 102, a patient interface system 10 may comprise apolyester front plate or window 279 having a TPE “macro” seal 280 and alow durometer nasal seal 281 comprising pillows, or a seal as disclosedin WO 2010/139014 A1, the entire contents of which are incorporatedherein by reference. A foam “micro” seal 275 may be attached to the seal280. A TPE or TPU headgear 276 may be provided to position the patientinterface system on the patient's head. Elastic webbing or ultrasonicdie cut spacer fabric 277 may be provided. A tube connect 278 may beconnected to a textile sock 282.

Patient Interface Systems—Headgear Strap and Tube Attachment

Referring to FIGS. 109-112, a headgear strap, e.g. a lower headgearstrap that is positioned under the patient's ears and loops through aslot in the crown strap, may be connected to an air delivery tube 298.The air delivery tube 298 may connect to an end of the headgear strap297, with gases being delivered through the headgear clip 299. The clips299, 300 may interface with the front plate. As shown in FIGS. 111 and112, the headgear strap 301 may be configured to deliver gases throughan air delivery tube 302 and the clips 303, 304 may be formed in such away that the strap 301 can be oriented either left (FIG. 111) to rightor right to left (FIG. 112).

Patient Interface Structure—Patient Interface Positioning SystemConnection

Referring to FIG. 114, the front plate 21 may include a plurality ofattachment locations 305 for the patient interface positioning system,e.g. headgear, and/or a rotatable attachment location 306 that providesadjustment of the angle between the patient interface structure, e.g.mask, and the patient interface positioning system, e.g. headgear. Theattachment locations may be in the form of rings 307.

Patient Interface Structure—Fascia

The fascia, frame or lens portion may comprise a fixed elbow connection,the elbow connection directed horizontally. Such an arrangement can beseen in, for example, FIG. 99. The fascia be structured and arranged tobe flipped or rotated, such that the direction of the elbow may bechanged from pointing to the left, for example, to pointing to theright. This means that the fascia may be symmetrical.

While the technology has been described in connection with what arepresently considered to be the most practical and preferred embodiments,it is to be understood that the invention is not to be limited to thedisclosed embodiments, but on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the invention. Also, the various embodiments described abovemay be implemented in conjunction with other embodiments, e.g., aspectsof one embodiment may be combined with aspects of another embodiment torealize yet other embodiments. Further, each independent feature orcomponent of any given assembly may constitute an additional embodiment.Furthermore, each individual component of any given assembly, one ormore portions of an individual component of any given assembly, andvarious combinations of components from one or more embodiments mayinclude one or more ornamental design features. In addition, while theinvention has particular application to patients who suffer from OSA, itis to be appreciated that patients who suffer from other illnesses(e.g., congestive heart failure, diabetes, morbid obesity, stroke,bariatric surgery, etc.) can derive benefit from the above teachings.Moreover, the above teachings have applicability with patients andnon-patients alike in non-medical applications.

1. A patient interface structure for delivery of respiratory therapy toa patient, comprising: a frame configured to conform to the shape of thepatient's face; a mouth cushion provided to the frame, the mouth cushiondefining a first breathing chamber and comprising a first sealingsurface configured to seal around the patient's mouth when the patientinterface structure engages the patient's face; a nasal cushionsupported by the mouth cushion, the nasal cushion comprising a secondsealing surface configured to seal the patient's nasal airways when thepatient interface structure engages the patient's face; and a channelseparating the first sealing surface from the second sealing surface. 2.A patient interface structure according to claim 1, wherein the channelcompletely separates the first sealing surface from the second sealingsurface.
 3. A patient interface structure according to claim 2, whereinthe first sealing surface is configured to move independently of thesecond sealing surface.
 4. A patient interface structure according toclaim 3, wherein the channel is configured to facilitate the firstsealing surface moving independently of the second sealing surface.
 5. Apatient interface structure according to claim 1, wherein the firstsealing surface defines a first aperture and the second sealing surfacedefines a second aperture.
 6. A patient interface structure according toclaim 5, wherein the nasal cushion defines a second breathing chamberseparate from the first breathing chamber.
 7. A patient interfacestructure according to claim 6, wherein the first breathing chamber andthe second breathing chamber communicate with each other by way of athird aperture.
 8. A patient interface structure according to claim 1,wherein the channel is configured to face the patient's face when thepatient interface structure engages the patient's face.
 9. A patientinterface structure according to claim 1, wherein the nasal cushionextends at least partially into the breathing chamber.
 10. A patientinterface structure according to claim 9, wherein at least a portion ofthe nasal cushion extends below an upper portion of the frame.
 11. Apatient interface structure according to claim 1, wherein the nasalcushion comprises a lower durometer material than the mouth cushion. 12.A patient interface structure according to claim 1, wherein the frame isa flexible plate.
 13. A patient interface structure according to claim12, wherein the flexible plate comprises a guide for aligning the mouthcushion.
 14. A patient interface structure according to claim 1, whereinthe mouth cushion comprises gusseted side walls.
 15. A patient interfacesystem, comprising: a patient interface structure according to claim 1;and a patient interface structure positioning system configured toposition, stabilize and secure the patient interface structure insealing engagement with the patient's face.
 16. A patient interfacestructure for delivery of respiratory therapy to a patient, comprising:a frame configured to conform to the shape of the patient's face; amouth cushion provided to the frame, the mouth cushion defining a firstbreathing chamber and comprising a first sealing surface configured toseal around the patient's mouth when the patient interface structureengages the patient's face; a nasal cushion supported by the mouthcushion, the nasal cushion defining a second breathing chamber, thenasal cushion comprising a second sealing surface configured to seal thepatient's nasal airways when the patient interface structure engages thepatient's face; and a channel between the first and second sealingsurfaces.
 17. A patient interface structure according to claim 16,wherein the first and second sealing surfaces are visually distinct. 18.A patient interface structure according to claim 17, wherein the channelprovides a demarcation between the first sealing surface and the secondsealing surface.
 19. A patient interface structure according to claim18, wherein the channel facilitates the first sealing surface movingindependently of the second sealing surface.
 20. A patient interfacestructure according to claim 16, wherein the channel is configured totraverse a space between the patient's nose and the patient's mouth whenthe patient interface structure engages the patient's face.
 21. Apatient interface structure according to claim 16, wherein the nasalcushion extends at least partially into the breathing chamber.
 22. Apatient interface structure according to claim 21, wherein at least aportion of the nasal cushion extends below an upper portion of theframe.
 23. A patient interface system, comprising: a patient interfacestructure according to claim 16; and a patient interface structurepositioning system configured to position, stabilize and secure thepatient interface structure in sealing engagement with the patient'sface.
 24. A patient interface structure for delivery of respiratorytherapy to a patient, comprising: a frame configured to conform to theshape of the patient's face; and a cushion provided to the frame, thecushion comprising a sealing surface configured to sealingly engage thepatient's face when the patient interface structure engages thepatient's face, the sealing surface comprising a channel that dividesthe cushion into a first sealing surface and a second sealing surface,the first sealing surface being configured to seal around the patient'smouth when the patient interface structure engages the patient's faceand the second sealing surface being configured to seal the patient'snasal airways when the patient interface structure engages the patient'sface. 25-27. (canceled)
 28. A patient interface structure according toclaim 24, wherein the first and second sealing surfaces are visuallydistinct.
 29. A patient interface structure according to claim 28,wherein the channel facilitates the first sealing surface movingindependently of the second sealing surface.
 30. A patient interfacestructure according to claim 24, wherein the channel is located on apatient engaging side of the cushion.
 31. A patient interface system,comprising: a patient interface structure according to claim 24; and apatient interface structure positioning system configured to position,stabilize and secure the patient interface structure in sealingengagement with the patient's face.